Vulnerability Note VU#886006

Squid vulnerable to buffer overflow via an overly long WCCP message

Overview

The Squid web proxy cache is vulnerable to a buffer overflow when handing overly long web cache communications protocol (WCCP) messages. Such messages could crash the Squid process and produce a denial of service condition.

Description

Squid functions as a web proxy and cache application for number of protocols. It supports WCCP to enable communications between routers and web caches. A recvfrom() call in the WCCP handling routines accepts more data than the buffer size may be able to handle. An attacker may be able to crash the Squid process by sending an overly-long WCCP message.

Impact

A remote unauthenticated attacker may be able to crash the Squid process and create a denial of service condition. Sites not using WCCP, which is disabled by default, are not affected.

Solution

Apply an update

Administrators should obtain an updated version of Squid from their vendor if WCCP is used.